A residual current operated circuit breaker with self-checking function

Abstract

The present invention discloses a residual current operated circuit breaker with a self-checking function, which includes a housing. Inside the housing, there are arranged a PCB control circuit assembly board, a residual current protection release, a zero-sequence current transformer, an alarm indicator light and a buzzer. On the PCB control circuit assembly board, there is arranged a main control chip and a thyristor connected to the main control chip. The thyristor is simultaneously connected to the residual current protection release. The zero-sequence current transformer, the alarm indicator light and the buzzer are respectively connected to the main control chip. The residual current circuit breaker with a self-checking function provided by the present invention can automatically perform periodic self-checking on whether there are faults in itself without manual intervention to further ensure the user's electricity consumption safety. Moreover, during the self-checking process of the present invention, the electrical connection state of the main circuit will not be disconnected, and the power supply continuity to related equipment can be ensured.

Description

Technical Field

[0001] The present invention relates to a circuit breaker, and more particularly to a residual current operated circuit breaker with a self-checking function. Background Art

[0002] As an important protection device for preventing electric shock accidents and leakage damage of electrical equipment in low-voltage distribution systems, residual current operated circuit breakers have been widely used. However, in actual applications, due to reasons such as non-standard installation and configuration, and poor product quality, circuit breaker damage or leakage protection function failure often occurs, which may lead to personal injury accidents or equipment damage accidents. Therefore, in order to ensure the effectiveness of the leakage protection function of the circuit breaker, the traditional inspection method is to manually operate the test button provided on the circuit breaker to verify the circuit breaker's ability to respond to ground faults.

[0003] However, in fact, most users do not regularly and actively verify the function of the circuit breaker because they find the operation troublesome. Moreover, manually operating the test button will interrupt the power supply continuity of the equipment, or cause economic losses to users. In addition, even if users are willing to manually verify the function of the circuit breaker every month, the verification cycle of one month is too long. If the leakage protection function of the circuit breaker fails within the month, it will bring great potential safety hazards to users' electricity consumption. Summary of the Invention

[0004] In view of this, the present invention provides a residual current operated circuit breaker with a self-checking function to solve the above-mentioned technical problems.

[0005] The technical solution adopted by the present invention to solve its technical problems is to provide a residual current operated circuit breaker with a self-checking function, which includes a housing, an operating handle provided on the top of the housing, a test button, a contact system provided in the housing, and an arc extinguishing chamber using the contact system. The contact system is connected to the operating handle. An incoming line terminal, an outgoing line terminal, a short-circuit protection mechanism, and an overload protection mechanism are also provided in the housing.

[0006] A PCB control circuit component board, a residual current protection release, a zero-sequence current transformer, an alarm indicator light, and a buzzer are also provided in the housing.

[0007] A main control chip and a thyristor connected to the main control chip are provided on the PCB control circuit component board. The thyristor is simultaneously connected to the residual current protection release. The zero-sequence current transformer, the alarm indicator light, and the buzzer are respectively connected to the main control chip.

[0008] As a preferred embodiment of the present invention, the specific model of the main control chip provided on the PCB control circuit component board is LT6713V.

[0009] As a preferred embodiment of the present invention, the main control chip includes a digital logic controller and a voltage regulator rectifier, a ground fault controller, an SCR trigger, a delay trigger, a timer, a low dropout linear regulator, and an LED indicator controller respectively connected to the digital logic controller;

[0010] The second pin of the main control chip is connected to the negative input pin of a first operational amplifier;

[0011] The third pin of the main control chip is connected to the positive input pin of the first operational amplifier;

[0012] The output terminal of the first operational amplifier is connected to the input terminal of a second operational amplifier, and the positive and negative input pins of the second operational amplifier are short-circuited; the output terminal of the first operational amplifier is also connected to the first pin of the main control chip;

[0013] The output terminal of the second operational amplifier is connected to the delay trigger;

[0014] The delay trigger is connected in series with the SCR trigger;

[0015] The SCR trigger is connected to the sixteenth pin of the main control chip;

[0016] The intersection point of the delay trigger and the SCR trigger is connected to the first port of the digital logic controller;

[0017] The second port of the digital logic controller is connected to the fifteenth pin of the main control chip;

[0018] The third port of the digital logic controller is connected to the fourteenth pin of the main control chip through a main level detection module;

[0019] The fourth port of the digital logic controller is connected to the thirteenth pin of the main control chip;

[0020] The fifth port of the digital logic controller is connected to the twelfth pin of the main control chip through the ground fault controller;

[0021] The sixth port of the digital logic controller is connected to the eleventh pin of the main control chip through the LED indicator controller;

[0022] The seventh port of the digital logic controller is connected to the ninth pin of the main control chip through the timer;

[0023] The eighth port of the digital logic controller is connected to the seventh pin of the main control chip through the first output terminal of the low dropout linear regulator, and is connected to the eighth pin of the main control chip through the second output terminal of the low dropout linear regulator.

[0024] As a preferred embodiment of the present invention, the test button includes a button body and a light guide column connected to the button body. The button body is disposed on the exposed surface of the housing, and the light guide column is disposed inside the housing.

[0025] As a preferred embodiment of the present invention, the test button is made of transparent plastic.

[0026] As a preferred embodiment of the present invention, the alarm indicator is disposed below the light guide column of the test button and is disposed opposite to the light guide column.

[0027] As a preferred embodiment of the present invention, the PCB control circuit component board is disposed at the bottom position inside the housing; the residual current protection release is disposed at the upper position of the PCB control circuit component board; the zero-sequence current transformer is disposed at the left position of the PCB control circuit component board.

[0028] As a preferred embodiment of the present invention, the alarm indicator is disposed on the housing, and the alarm indicator is connected to the main control chip disposed on the PCB control circuit component board through a wire;

[0029] As a preferred embodiment of the present invention, the buzzer is disposed on the PCB control circuit component board.

[0030] The residual current circuit breaker with self-checking function provided by the present invention can automatically perform periodic self-checking on whether there is a fault in itself without manual intervention to further ensure the user's electricity safety. Moreover, the present invention will not disconnect the electrical connection state of the main circuit during the self-checking process, and can ensure the power supply continuity of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 is a three-dimensional structure diagram of a residual current operated circuit breaker with self-checking function provided by an embodiment of the present invention;

[0032] Figure 2 is a schematic diagram of the internal structure of a residual current operated circuit breaker with self-checking function provided by an embodiment of the present invention Figure 1 ;

[0033] Figure 3 is a schematic diagram of the internal structure of a residual current operated circuit breaker with self-checking function provided by an embodiment of the present invention Figure 2 ;

[0034] Figure 4 is a top view of a residual current operated circuit breaker with a self-checking function provided by an embodiment of the present invention;

[0035] Figure 5 is a schematic structural diagram of a test button on a residual current operated circuit breaker with a self-checking function provided by an embodiment of the present invention;

[0036] Figure 6 is a schematic internal structure diagram of a main control chip provided inside a residual current operated circuit breaker with a self-checking function provided by an embodiment of the present invention;

[0037] Figure 7 is a function description table of each pin of the main control chip inside the residual current operated circuit breaker provided by an embodiment of the present invention. Detailed implementation manners

[0038] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without making creative efforts shall fall within the protection scope of the present invention.

[0039] It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments may be combined with each other.

[0040] Next, the present invention will be further described in conjunction with the accompanying drawings and specific embodiments, but it is not a limitation of the present invention.

[0041] Please refer to Figure 1 、 Figure 2 and Figure 4 , a residual current operated circuit breaker with a self-checking function provided by an embodiment of the present invention includes a housing 1, an operating handle 2 provided at the top of the housing 1, a test button 3, a contact system 4 provided inside the housing 1, and an arc extinguishing chamber 5 using the contact system 4. The contact system 4 is connected to the operating handle 2. An incoming line terminal 6, an outgoing line terminal 7, a short-circuit protection mechanism 8, and an overload protection mechanism 9 are further provided inside the housing 1.

[0042] Please refer to Figure 3 , a PCB control circuit component board 11, a residual current protection release 10, a zero-sequence current transformer 12, an alarm indicator light 13, and a buzzer 113 are further provided inside the housing 1 of the residual current operated circuit breaker provided in this embodiment;

[0043] On the PCB control circuit component board 11, a main control chip 112 and a thyristor 111 connected to the main control chip 112 are provided; the thyristor 111 is also connected to the residual current protection release 10; the zero-sequence current transformer 12, the alarm indicator light 13 and the buzzer 113 are respectively connected to the main control chip 112.

[0044] In the above technical solution, the operating handle 2, the test button 3, the contact system 4, the arc extinguishing chamber 5, the incoming line terminal 6, the outgoing line terminal 7, the short-circuit protection mechanism 8 and the overload protection mechanism 9 are all devices commonly used in circuit breakers in this technical field and are prior arts. Therefore, the internal structures of the short-circuit protection mechanism 8, the overload protection mechanism 9 and the contact system 4 are not described herein. Moreover, for those skilled in the art of this technical field, the connection manners between these existing devices applied to circuit breakers are well known to those skilled in the art. Therefore, the connection manners such as the connection manner between the contact system 4 and the operating handle 2 and the connection manner between the short-circuit protection mechanism 7 and the overload protection mechanism 8 are not described herein.

[0045] In order to enable the residual current operated circuit breaker provided in this embodiment to have a good self-checking function, the applicant independently developed the main control chip 112 with the model number LT6713V. Please refer to Figure 6 , this main control chip 112 is actually a leakage protection circuit with a self-checking function. The main control chip 112 includes:

[0046] A digital logic controller 1121 and a voltage regulator rectifier 1122, a ground fault controller 1123, an SCR trigger 1124, a delay trigger 1125, a timer 1126, a low dropout linear voltage regulator 1127 and an LED indicator controller 1128 respectively connected to the digital logic controller 1121;

[0047] The second pin of the main control chip 112 is connected to the negative input pin of a first operational amplifier 1129;

[0048] The third pin of the main control chip 112 is connected to the positive input pin of the first operational amplifier 1129;

[0049] The output end of the first operational amplifier 1129 is connected to the input end of a second operational amplifier 1130, and the positive and negative input pins of the second operational amplifier 1130 are short-circuited; the output end of the first operational amplifier 1129 is also connected to the first pin of the main control chip 112;

[0050] The output end of the second operational amplifier 1130 is connected to the delay trigger 1124;

[0051] The delay trigger 1124 is connected in series with the SCR trigger 1125;

[0052] The SCR trigger 1125 is connected to the sixteenth pin of the main control chip;

[0053] The intersection point of the delay trigger 1124 and the SCR trigger 1125 is connected to the first port 100 of the digital logic controller 1121;

[0054] The second port 200 of the digital logic controller 1121 is connected to the fifteenth pin of the main control chip 112;

[0055] The third port 300 of the digital logic controller 1121 is connected to the fourteenth pin of the main control chip 112 through a main level detection module 1131 (MLD);

[0056] The fourth port 400 of the digital logic controller 1121 is connected to the thirteenth pin of the main control chip 112;

[0057] The fifth port 500 of the digital logic controller 1121 is connected to the twelfth pin of the main control chip 112 through the ground fault controller 1123;

[0058] The sixth port 600 of the digital logic controller 1121 is connected to the eleventh pin of the main control chip 112 through the LED indicator controller 1128;

[0059] The seventh port 700 of the digital logic controller 1121 is connected to the ninth pin of the main control chip 112 through the timer 1126;

[0060] The eighth port 800 of the digital logic controller 1121 is connected to the seventh pin of the main control chip 112 through the first output terminal of the low dropout linear regulator 1127, and is connected to the eighth pin of the main control chip 112 through the second output terminal of the low dropout linear regulator 1127.

[0061] Figure 7 It is a function description table of each pin of the main control chip 112. Please refer to Figure 6 and Figure 7 , Figure 6 The Amp Out (operational amplifier output pin) in corresponds to the first pin of the main control chip;

[0062] Figure 6 The VFB (negative input pin of the operational amplifier) in corresponds to the second pin of the main control chip;

[0063] Figure 6 The V+ (positive input pin of the operational amplifier) in corresponds to the third pin of the main control chip;

[0064] Figure 6The VCC (analog power supply) in it corresponds to the fourth pin of the main control chip;

[0065] Figure 6 The A-GND (analog ground) in it corresponds to the fifth pin of the main control chip;

[0066] Figure 6 The D-GND (digital ground) in it corresponds to the sixth pin of the main control chip;

[0067] Figure 6 The VDD (digital power supply) in it corresponds to the seventh pin of the main control chip;

[0068] Figure 6 The REF (reference voltage) in it corresponds to the eighth pin of the main control chip;

[0069] Figure 6 The CAP (clock capacitor pin) in it corresponds to the ninth pin of the main control chip;

[0070] The tenth pin of the main control chip is left floating;

[0071] Figure 6 The LED (LED indicating the working state of the GFCI) in it corresponds to the eleventh pin of the main control chip;

[0072] Figure 6 The GF-test (loop self-checking test square wave, simulating the grounded fault state) in it corresponds to the twelfth pin of the main control chip;

[0073] Figure 6 The SCR-test (GFCI loop SCR detection feedback pin) in it corresponds to the thirteenth pin of the main control chip;

[0074] Figure 6 The MLD (main level detection, touching the ground can trigger manual self-checking and reset the timer) in it corresponds to the fourteenth pin of the main control chip;

[0075] Figure 6 The EN (self-checking enable pin, grounding can turn off the digital logic controller) in it corresponds to the fifteenth pin of the main control chip;

[0076] Figure 6 The SCR-drv (when a grounded fault is detected, drive the thyristor to trip) in it corresponds to the sixteenth pin of the main control chip.

[0077] It should be noted that the GFCI is a ground fault current leakage protector, that is, the residual current operated circuit breaker with self-checking function provided in this embodiment. The SCR is a thyristor (thyristor rectifier).

[0078] After the user connects the residual current operated circuit breaker provided in this embodiment to a live low-voltage power distribution system, the user closes the operating handle 2 to form a leakage protection circuit inside the circuit breaker. After the operating handle 2 is closed, under the control of the main control chip 112, the circuit breaker starts the first self-check, and then detects faults of key components in the leakage protection circuit at set intervals, such as every 15 minutes. The key components described here include the zero-sequence current transformer 12, the main control chip 112, the residual current protection release 10, and the thyristor 111. During the self-check process, if any key component is detected to have a fault, the main control chip 112 will confirm that the self-check result is a self-check failure. At this time, the main control chip 112 will drive the buzzer 113 to alarm, such as driving the buzzer 113 to alarm continuously for 60 s, and trigger the thyristor 111 to control the residual current protection release 10 to trip forcibly, so that the residual current operated circuit breaker disconnects to ensure electrical safety.

[0079] It should be noted that when the main control chip 112 detects that the thyristor 111 or the residual current protection release 10 itself fails, the residual current operated circuit breaker can no longer control the residual current protection release 10 to trip forcibly through the thyristor 111 to disconnect the residual current operated circuit breaker. At this time, the main control chip 112 will control the buzzer 113 to alarm continuously and control the alarm indicator 13 to flash continuously to prompt the user to take further measures to ensure electrical safety.

[0080] In the above technical solution, preferably, please refer to Figure 5 , the test button 3 includes a button body 32 and a light guide column 31 connected to the button body 32. The button body 32 is arranged on the exposed surface of the housing 1, and the light guide column 31 is arranged inside the housing 1.

[0081] Since the alarm indicator 13 is arranged inside the housing 1 of the residual current operated circuit breaker, in order to lead the light emitted by the alarm indicator 13 out of the housing 1 so that the user can clearly see the alarm status of the alarm indicator 13 in the first time, preferably, the alarm indicator 13 is arranged at a position below the test button 3 and is arranged opposite to the light guide column 31. In order to further improve the light guiding effect, more preferably, both the button body 32 and the light guide column 31 of the test button 3 are made of transparent plastic.

[0082] In order to reduce the wiring complexity inside the residual current circuit breaker as much as possible, preferably, the PCB control circuit component board 11 is arranged at the bottom position inside the housing 1; the residual current protection release 10 is arranged at a position above the PCB control circuit component board 11; the zero-sequence current transformer 12 is arranged at the left position of the PCB control circuit component board 11.

[0083] In the above technical solution, in order to further reduce the wiring space inside the housing to reduce the overall volume of the residual current circuit breaker, the buzzer 113 may preferably be arranged on the PCB control circuit component board 11.

[0084] In addition, in order to enhance the alarm indication effect of the alarm indicator 13, the alarm indicator 13 may also be arranged on the housing 1 of the residual current circuit breaker. The alarm indicator 13 is connected to the main control chip 112 arranged on the PCB control circuit component board 11 through a wire. Similarly, the buzzer 113 is connected to the main control chip 112 through a wire.

[0085] In summary, the residual current circuit breaker with self-checking function provided by the present invention can automatically perform periodic self-checking on whether there is a fault in itself without manual intervention to further ensure the user's power consumption safety. Moreover, during the self-checking process of the present invention, the electrical connection state of the main circuit will not be disconnected, and the power supply continuity of related equipment can be ensured.

[0086] The above are only the preferred embodiments of the present invention, and do not limit the implementation manners and protection scope of the present invention accordingly. For those skilled in the art, it should be able to realize that the solutions obtained by equivalent substitution and obvious changes made by using the description and illustrated content of the present invention should all be included in the protection scope of the present invention.

Claims

1. A residual current operated circuit breaker with a self-checking function, comprising a housing, an operating handle arranged at the top of the housing, a test button, a contact system arranged in the housing, and an arc extinguishing chamber using the contact system. The contact system is connected to the operating handle. An incoming line terminal, an outgoing line terminal, a short-circuit protection mechanism, and an overload protection mechanism are further arranged in the housing. It is characterized in that: A PCB control circuit component board, a residual current protection release, a zero-sequence current transformer, an alarm indicator light, and a buzzer are further arranged in the housing; A main control chip and a thyristor connected to the main control chip are arranged on the PCB control circuit component board; the thyristor is simultaneously connected to the residual current protection release; the zero-sequence current transformer, the alarm indicator light, and the buzzer are respectively connected to the main control chip; The specific model of the main control chip arranged on the PCB control circuit component board is LT6713V; the buzzer is arranged on the PCB control circuit component board; The main control chip includes a digital logic controller, a voltage stabilizing rectifier, a ground fault controller, an SCR trigger, a delay trigger, a timer, a low-dropout linear voltage regulator, and an LED indicator light controller which are respectively connected to the digital logic controller; The second pin of the main control chip is connected to the negative input pin of a first operational amplifier; The third pin of the main control chip is connected to the positive input pin of the first operational amplifier; The output end of the first operational amplifier is connected to the input end of a second operational amplifier, and the positive and negative input pins of the second operational amplifier are short-circuited; the output end of the first operational amplifier is simultaneously connected to the first pin of the main control chip; The output end of the second operational amplifier is connected to the delay trigger; The delay trigger is connected in series with the SCR trigger; The SCR trigger is connected to the sixteenth pin of the main control chip; The intersection point of the delay trigger and the SCR trigger is connected to the first port of the digital logic controller; The second port of the digital logic controller is connected to the fifteenth pin of the main control chip; The third port of the digital logic controller is connected to the fourteenth pin of the main control chip through a main level detection module; The fourth port of the digital logic controller is connected to the thirteenth pin of the main control chip; The fifth port of the digital logic controller is connected to the twelfth pin of the main control chip through the ground fault controller; The sixth port of the digital logic controller is connected to the eleventh pin of the main control chip through the LED indicator light controller; The seventh port of the digital logic controller is connected to the ninth pin of the main control chip through the timer; The eighth port of the digital logic controller is connected to the seventh pin of the main control chip through the first output end of the low-dropout linear voltage regulator, and is connected to the eighth pin of the main control chip through the second output end of the low-dropout linear voltage regulator.

2. The residual current operated circuit breaker with a self-checking function according to claim 1, It is characterized in that, The test button includes a button body and a light guide column connected to the button body. The button body is disposed on the exposed surface of the housing, and the light guide column is disposed inside the housing.

3. The residual current operated circuit breaker with self-checking function according to claim 2, characterized in that, the test button is made of transparent plastic.

4. The residual current operated circuit breaker with self-checking function according to claim 2, characterized in that, the alarm indicator light is disposed at a position below the test button and is disposed opposite to the light guide column.

5. The residual current operated circuit breaker with self-checking function according to claim 1, characterized in that, the PCB control circuit component board is disposed at the bottom position inside the housing; the residual current protection release is disposed at a position above the PCB control circuit component board; the zero-sequence current transformer is disposed at the left position of the PCB control circuit component board.

6. The residual current operated circuit breaker with self-checking function according to claim 1, characterized in that, the alarm indicator light is disposed on the housing, and the alarm indicator light is connected to the main control chip disposed on the PCB control circuit component board through a wire.

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